Improved MESFET/pHEMT Models and Their Comprehensive Comparison With Standard Ones

In the paper, we suggest several new updates to the equations that ordinarily describe the MESFETs and pHEMTs in both DC and time domains. We have composed some novel forms of the equations that are especially convenient for accurate describing transconductance voltage dependences, which is important for realistic modeling the low noise amplifiers with pHEMTs including calculations of their IP3 points. In other words, the attention is not only directed to the precision of the equation themselves, but also to the accuracy of the derivatives of them with respect to both gate-source and gate-drain voltages (up to the third order). The paper contains comprehensive comparisons of our recently updated models with our previous one and many others; two pHEMTs have been used for comparisons: the first working from 1 GHz up to 18 GHz, and the second operating at the frequencies greater than 100 GHz. Both DC characteristics and high-frequency s-parameters have been compared, and the comparisons show that the precision of our model modifications is at least comparable with the model like TriQuint ones. (And they seem even better in modeling input reflection coefficient, e.g.).